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41.
The microstructural properties of the β-FeSi2/FeSi structure prepared from a molten salt have been characterized using transmission electron microscopy (TEM). The β-FeSi2 films were grown on FeSi substrates at the heat treatment temperature of 900 °C from 1 min to 24 h using the molten salt technique. It is found that the films consisted of a thin surface layer and a thick underlying layer with columnar-shaped domains. The crystallographic directions of the domains are mostly randomly oriented. The β-FeSi2 domains in the film, however, have specific crystallographic orientation relationships with the adjoining domains and the FeSi substrate. A high density of the stacking faults on the β-FeSi2 (100) planes was also observed through the films. Moreover, the growth evolution of the β-FeSi2 domains, the defect characteristics and the formation mechanism of the defects are discussed. 相似文献
42.
β-FeSi2 layers have been successfully grown using a molten salt method for the first time. It was found that single phase and homogeneous β-FeSi2 layers with a columnar domain structure can be grown on FeSi substrates. The layer thickness was demonstrated to be controllable by the growth temperature and time, and was diffusion controlled. It was shown that the layers were void- and crack-free compared to similar layers grown on Fe substrates: this difference is explained in terms of Fe diffusion. This vacuum-free simple growth technique is useful for the fabrication of large area semiconductor devices at low cost. 相似文献
43.
M Ohishi M Ueda H Rakugi A Okamura T Naruko AE Becker K Hiwada A Kamitani K Kamide J Higaki T Ogihara 《Canadian Metallurgical Quarterly》1997,96(10):3328-3337
BACKGROUND: Balloon injury models in rat have shown enhanced expression of ACE in the developing neointima. However, neointimal lesions in human coronary arteries are complex due to atherosclerosis and different types of wall laceration. This study was designed to investigate whether ACE is present in the neointima of humans, including patients with restenosis after percutaneous transluminal coronary angioplasty (PTCA). METHODS AND RESULTS: Thirty-seven sites with angioplasty injury, obtained at autopsy, were studied using immunocytochemical techniques. Sites with injury limited to a fibrous plaque and those with injury extending into the media (<2 months after PTCA) showed fibrocellular repair tissue composed mainly of smooth muscle cells that were distinctly positive for ACE. In cellular reactions at the site of injury limited to the atheromatous plaque (<2 months after PTCA), the expression of ACE appeared first in accumulated macrophages; once smooth muscle cells appeared in the repair tissue, they also expressed ACE. At a later stage (3 months after PTCA), the number of cells with ACE expression decreased markedly; from 7 months on, ACE was no longer expressed within the repair tissue. Basically, there were no differences with regard to ACE expression during the healing process after PTCA between segments with and those without angiographic evidence of restenosis. CONCLUSIONS: These results show that PTCA injury in humans results in upregulation of ACE at sites of active repair and, therefore, ACE could play an important role as one of the mediators of the healing process after PTCA. 相似文献
44.
A new spectral attenuation measurement system using a Fourier transform spectrometer is developed. The Fourier transform spectral attenuation measurement (FT-SAM) system makes the signal acquisition time for a wide wave-length range of 1.0?4.2? much shorter than measurement with a conventional dispersive spectral attenuation measurement system. The spectral attenuation for a fluoride glass single-mode fibre, with a minimum loss of 3±1 dB/km at 2.5?m, is measured with this system. 相似文献
45.
T Ohishi M Takahashi K Kushida H Hoshino T Tsuchikawa K Naitoh T Inoue 《Canadian Metallurgical Quarterly》1998,118(3):126-130
Clinical diagnosis of canine nasal mite (Pneumonyssoides caninum) infection is difficult due to the mite's location in the caudal nasal cavity and frontal sinuses. The current study was performed to evaluate the efficacy of milbemycin oxime in treating dogs with nasal mite infection. A prospective open uncontrolled study included 20 dogs with case histories indicating possible nasal mite infection. Inclusion criteria consisted of either nasal mites being demonstrated (group 1, four dogs), or suspicious clinical signs with no other apparent causes, combined with eosinophilia (group 2, 16 dogs). Milbemycin oxime 1 mg/kg was given orally three times at 10-day intervals. In 17 (85 per cent) dogs, clinical signs resolved completely following milbemycin therapy; within 10 days of the first treatment in 13 cases (group 1, four dogs; group 2, nine dogs) and within 14 days in four cases. In the remaining three dogs clinical signs persisted but were diminished. 相似文献
46.
T Taoka S Iwasaki H Uchida A Fukusumi H Nakagawa K Kichikawa K Takayama T Yoshioka M Takewa H Ohishi 《Canadian Metallurgical Quarterly》1998,22(4):514-517
Rifampicin synoviorthesis has been empirically used for the treatment of haemophilic synovitis for some time. This paper reports on the experience of three Latin American centers with this treatment and compares it with radioactive synoviorthesis results. Chemical synoviorthesis with rifampicin is best indicated in younger patients (< 15 years) and small joint (ankles and elbows). 相似文献
47.
A homologue of Saccharomyces cerevisiae Dpm1p is not sufficient for synthesis of dolichol-phosphate-mannose in mammalian cells 总被引:1,自引:0,他引:1
S Tomita N Inoue Y Maeda K Ohishi J Takeda T Kinoshita 《Canadian Metallurgical Quarterly》1998,273(15):9249-9254
Dolichol-phosphate-mannose (Dol-P-Man) serves as a donor of mannosyl residues in major eukaryotic glycoconjugates. It donates four mannosyl residues in the N-linked oligosaccharide precursor and all three mannosyl residues in the core of the glycosylphosphatidylinositol anchor. In yeasts it also donates one mannose to the O-linked oligosaccharide. The yeast DPM1 gene encodes a Dol-P-Man synthase that is a transmembrane protein expressed in the endoplasmic reticulum. We cloned human and mouse homologues of DPM1, termed hDPM1 and mDPM1, respectively, both of which encode proteins of 260 amino acids, having 30% amino acid identity with yeast Dpm1 protein but lacking a hydrophobic transmembrane domain, which exists in the yeast synthase. Human and mouse DPM1 cDNA restored Dol-P-Man synthesis in mouse Thy-1-deficient mutant class E cells. Mouse class E mutant cells had an inactivating mutation in the mDPM1 gene, indicating that mDPM1 is the gene for class E mutant. In contrast, hDPM1 and mDPM1 cDNA did not complement another Dol-P-Man synthesis mutant, hamster Lec15 cells, whereas yeast DPM1 restored both mutants. Therefore, in contrast to yeast, mammalian cells require hDPM1/mDPM1 protein and a product of another gene that is defective in Lec15 mutant cells for synthesis of Dol-P-Man. 相似文献
48.
Y Akao H Mizoguchi K Misiura WJ Stec M Seto N Ohishi K Yagi 《Canadian Metallurgical Quarterly》1998,58(17):3773-3776
49.
50.
We measured the interfacial tension of
3
He-4
He mixtures under pressure of 21 atm down to about 0.2K by using the resonance of the interfacial wave and found that the decrease from absolute zero is proportional to T2
up to about 0.4 K. From the simple extrapolation of this T2-dependence the interfacial tension at absolute zero is obtained as
i
(0) = 19.3 ± 1.3 mdyne/cm. Compared with saturated vapor pressure, the interfacial tension at absolute zero decreases by about 20%, and the coefficient of the T2-dependence does not depend strongly on pressure. The large T2-dependence both at saturated vapor pressure and at 21 atm may be attributable to the change in density difference between the two phases. 相似文献